Time-controlled heat-regulator for furnaces



H. F. GREENAWALT. TIME CONTROLLED HEAT REGULATOR FOR FURNACES.

APPLICATION FILED FEB. I5, I918.

Patnted Feb. 24, 1920.

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HARRYF. GREENAWALT, OF PHILADELPHIA, PENNSYLVANIA.

TIME-CONTROLLED HEAT-REGULATOR ron FURNACES.

Specification of Letters Patent.

Patented Feb. 24, 19 20.,

Application filed February 15, 1918. Serial No. 217,391.

To all whom it may concern;

Be it known that I, HARRY F. GREENA- WALT, a citizenof the United States, and a resident of Philadelphia, county of Philadelphia, and State of Pennsylvania, have invented a certain new and usefulTime- Controlled Heat-Regulator for Furnaces, of which the, following is a specification.

The principal object of the present in-' vention is to provide a simply constructed and efiiciently operating mechanism designed to automatically close andopen, at a predetermined time, the fire-door and the draft-door, respectively, of a I furnace. Other and further objects of the present invention reside in the provision of certain new and novel arrangements, combination and connection of parts for rendering the invention practical according to commercial standards.

The invention consists of the" improvements hereinafter described and finally claimed. 7 v I The nature, characteristic features and scope of the invention will be more fully understood from the following description taken in connection with the accompanying drawings forming part hereof and in which:

Figure 1 is a View in front elevation of a furnace equipped witha regulator, showing one embodiment of the principles of the present invention.

Fig. 2 is a View in side elevation thereof.

Fig. 3 is a view in section ofv a time-piece and its complemental casing.

Fig. 4 is a view in section taken upon the line H of Fig. 3;

Fig. 5 is a fragmentary view in front elevation of the spring actuated fire-door.

-- Fig. 6 is a similar view of the spring actuated draft-door. I

' Fig. 7 is a perspective view of the firedoor. detent. V

, Fig. 8 is a similar view of the draft-door release. 1 V

Fig. 9 is a fragmentary view in side elevation of the draft-door illustrating the relation of parts prior to the release being operated, and

Fig. 10 is a fragmentary view in cross-' section illustrating a position of the alarmarbor extension herelnafter referred to.

or the purpose of illustrating my 1nvention, I have shown in the accompanying 'shaped to arrest said door.

drawings one form thereof which is at present preferred by me, since the same has been found in practice to give satisfactory and reliable results, although it is to be understood that the various instrumentalities of which my invention consists can be variously arranged and organized and that my invention is not'limited to the precise arrangement and organization of the instrumentalities as herein shown and described. In the drawings 10 designates a furnace having the usual fire-door 11 and draftdoor 12, which doors are provided With hinge-lugs 13 having pivotal relation, by means of pintles, with hinge-lugs 15 upon the front plate of the furnace. According to the present invention, one pintle of each of said doors is removed and a pintle 16 substituted therefor. The drawings show this substitution as having been made with respect to the uppermost pintles. Such pintles proj ect well through the hinge-lugs and are screw-threaded for nut reception. Around each pintleis coiled a spring 17 one end of each spring being caused to impinge against a door and the opposite end against the front plate of the furnace. As clearly shown in Fig. 5, the ends of the spring freely bear against the fire-door and furnace-plate so that the tendency of the spring is to maintain said door in closed position. In Fig. 6, the ends of the spring are fixed, as by screws 18 or equivalent devices, to the draft-door and furnace-plate, so that the tendency of said spring is to maintain said door in open position. By means of the nuts 19 the springs 17 may be tightened to develop friction both between the coils of the spring andbetween the members 15 and 13' whereby the doors 11 and 12 are caused to move less quickly. Obviously by loosening the nuts 19 an opposite effect is procured. No other alteration of a standardfurnace is required in the application thereto of the regulator of the present invention. In order to maintain the fire-door in open position against the action of its complemental spring, a detent is employed, see Fig. 7, one end of which has pivotal relation as at 21 with the front plate of the furnace and the opposite end of which is As clearly shown in Fig. 7, such detent comprises an elongated strap 22 having its ends extended at right angles in opposite, directions of which the end 23 is apertured to accommodate a pivot member and of which the other thereof engaging a catch 27 on the furnace plate, see F ig; 9. In order to permit the draft-door to assume an open position through the cooperation of its complemental: spring, a release in the form of cam, see

Fig: 8, is'employed, pivoted as at, 28to the furnace-plate; Asclearly shown in Fig. 8, such; release, comprises an angular-shaped member provided with, a cam portion 291 which is positioned in abutting relation with the underside of the lip 26, of; thefurnace door., To the rear of the cam surface, said release is" provided with a projection. 30.

When the release is operated around its pivot ,point in a manner to presently appea'r,ftl1e,camsurface raises the lip 26 free of; the catch 27 whereupon the spring of the door causes the same to assume an open position. The projection 30 serves the functionofinitially starting the outward movement of the door simultaneously with the raising of the lip from its seat upon the catch 27".

A description will now be given of the detent and cam operating mechanism. Suspended above the furnace, as by the rafters 31;, is a housing or casing 32 containing a time-piece 33 of the type styled alarm: clocks, the front of the casing having an opening therethrough in which thetimepiece is mounted with its face exposed through said opening. In order to securely sustain ,a the time-piece in position, use is made of a clamping device shown in the drawings as comprising a band 34 fitted over theItime-piece ofwhich one end is apertured for engagement With therhook 35 of; a bolt 36 penetrating the casing bottom and; securedin position by means of anut 37 and a lock-nut 38,, and theother; end of which;has; fixed engagement with-the slotted end; 39; of abolt 40. which passes through an opening inqthe:v casin bottom: and may be adjusted; vertically t erethrough by" means of the nut: 41. Theialarm winding-key complemental to the; arbor of the ti'me-p1ece,.is

'32.;LThe arbors for alarm; setting, time winding and timesetting are similarly providedgwith extension arbors as clearly illustrated in-,F1g. 3; A. partition aoumaybe pl'esent within the: casing; to serve} as a bearing-for the arbor extensions. The alarmarbor extension 42 is provided with a laterally extended 7 opening 7. L7 therethrough, see Figs. 3,41and"l0"to"accominodate a cord, belt, rope, chainor similar medium which passes therethronghl' "the drawings, a chain 48 is illustrated. Such chain, which is continuous, passes horizontally through thecasing sides over pulleys 49 journaled to the casing outer sides and then passes vertically before the, furnace-plate, one, end of said chaincbeing secured to thefire-door c'letent and: the other 7 endgbeing; connectcdto thefifdamperedoor am,,, Figs. 1 and 2-. The time-piececasingjmay beprovirlediwith a, door 50; for gaining-access to the interior. thence-fa l a A- description; will: now. be giyenof themoderof operation of the above] described regulator; The alarm is set, for-the desired hour ofescapemenhthe: furnace. fire. banked,

thev firesdo r. being causedto. remain. in, open positionby reason ofithe: pivotal. detentguthe damper door ofv course beingtin closedlposi, tion, arbor, the arbor extensionrpartially rotates so as to, cause the, vertical, runs of the;-.chain to bedrawn upwardly, seeEi 10,- thus raisingthe detent freelofithe; rerdoor to; permit it to close by reason of itsicomple: mental. spring and. at' theisame, time. causing the. damper-doorfcam, to raise-the. lip there: of from its catch to permit the dampen-door sprin to moveitto: openvpositionr,

It will now, be; apparent that I have do: vised a novel; and useful construction which embodies.- the-features, of advantage enumere ated as desirable in the statementcof the. in vention-and: the, above description, and wliile With, the escapemenn of; the alarm I- have in the-presentinstance. shownand described" the, preferred; embodiment there;- of which has been found in. practice to; give satisfactoryand reliable, results, it is tobe understood, that, the same is. susceptiblefof modification various. particulars without departing from. the spiritxor. scope of; the

invention or sacrificing-anyLof; its-advan ta es.. at I claimisg;

Apparatus. of the) character stated, com- 7 prising in combination a furnace equipped with complementalfire; and, draft doors, a spring for closing the fire door when-released and: a spring foropenin'g the draft door when released, a detent pivoted to said furnace the for-maintaining .saiddoor closed, a. cam

pivoted; to the -.furnace; and; adapted when operatedcto:movegsaidl lipi over. said catch to 1 release the; draft door, a time-setprime mover having an apertured extension arbor and a continuous flexible connection passing through said aperture one end of which connection is secured to said detent and of which the other end of said connection is secured to said cam whereby upon operation of said arbor the intermediate portion of said connection is Wound around said arbor to cause the respective ends of said connection to move said detent and cam around their respective pivots for releasing said 10 doors.

In testimony whereof, I have hereunto signed my name.

HARRY F. GREENAWALT. 

